The IUPAC code
The International Union of Pure and Applied Chemistry (IUPAC) defined
the standard code for representing protein or DNA sequences.
Nucleic IUPAC Code
| Code |
Nucleotide |
|---|
| A |
Adenine |
| C |
Cytosine |
| G |
Guanine |
| T |
Thymine |
| U |
Uracil |
| R |
Purine (A or G) |
| Y |
Pyrimidine (C, T, or U) |
| M |
C or A |
| K |
T, U, or G |
| W |
T, U, or A |
| S |
C or G |
| B |
C, T, U, or G (not A) |
| D |
A, T, U, or G (not C) |
| H |
A, T, U, or C (not G) |
| V |
A, C, or G (not T, not U) |
| N |
Any base (A, C, G, T, or U) |
Peptidic one and three letters IUPAC code
| 1-letter |
3-letters |
Amino acid |
|---|
| A |
Ala |
Alanine |
| R |
Arg |
Arginine |
| N |
Asn |
Asparagine |
| D |
Asp |
Aspartic acid |
| C |
Cys |
Cysteine |
| Q |
Gln |
Glutamine |
| E |
Glu |
Glutamic acid |
| G |
Gly |
Glycine |
| H |
His |
Histidine |
| I |
Ile |
Isoleucine |
| L |
Leu |
Leucine |
| K |
Lys |
Lysine |
| M |
Met |
Methionine |
| F |
Phe |
Phenylalanine |
| P |
Pro |
Proline |
| S |
Ser |
Serine |
| T |
Thr |
Threonine |
| W |
Trp |
Tryptophan |
| Y |
Tyr |
Tyrosine |
| V |
Val |
Valine |
| B |
Asx |
Aspartic acid or Asparagine |
| Z |
Glx |
Glutamine or Glutamic acid |
| X |
Xaa |
Any amino acid |